Tear Jerker / Majin Tantei Nougami Neuro

  • The look on Higuchi's face when he sees that his parents are dead. As a child Higuchi's parents became complete shut-ins thanks to being obsessed with an MMORPG. In an attempt to get his parents to get off the computer and spend more time in the real world, Higuchi decided to hack into the game's system and crash the whole thing. Unfortunately his parents were so invested in the virtual world that they ended up Driven to Suicide. The final Mood Whiplash that ends the flashback was the tipping point.
  • Sasazuka's death, especially how Sicks kills him is equally sad.
  • Sai's death, he decides to turn into the late Sasazuka to give her some advice, which tears her up greatly.
    • Ai's death, so sudden and that he lost his Only Friend.
  • Fumio Honjo's suicide, he was a man who sold himself to the embodiment of evil by selling out his daughter to his twisted experiments and went insane till he finally killed himself when he realized how low he fell.
  • Setsuna's death, her brain degenerated till she died, Harukawa lived with the guilt of not saving her. The revelation that Sicks had a hand in this, makes it all the more tragic.
    • The entire conclusion of the HAL arc, really - the fact that, even if his plan had succeeded, Harukawa wouldn't have been able to meet her again in his lifetime; HAL knowing it's impossible, but still having to try, to the point where it sounds like he's asking Yako for a Mercy Kill by telling her to delete him; and finally, HAL seeing a vision of Setsuna in the split second before he's wiped out.
  • Yako's goodbye to Neuro.
  • Genuine's death to protect Sicks' secrets.
  • The death of Miyasako's grandfather.
  • Towards its end, the manga version pulls out all the stops. Sasazuka's death at the hands of Sicks, Honjou's suicide, Yako's subsequent breakdown and the death of X shortly after he finally regains his memories of Ai. It's really hard to choose which is worst.
    • Sai's last transformation being Sasazuka and his "I don't regret anything" speech.